Sn-15Cu-xNi合金组织及油润滑磨损行为

Microstructure and tribological properties of Sn-15Cu-xNi alloy

利用电感耦合等离子发射光谱仪、场发射电子探针、场发射扫描电镜、激光扫描共聚焦显微镜、布氏硬度计、多功能摩擦磨损试验机,研究Sn-15Cu-xNi合金的组织及油润滑磨损行为。结果表明:Sn-15Cu合金中的硬质颗粒为Cu_(3)Sn+Cu_(6)Sn_(5)组成的板条状包晶组织,添加0.1%Ni可以细化Cu_(3)Sn并使Cu_(6)Sn_(5)包覆层增厚,添加0.5%Ni可以完全抑制Cu_(3)Sn的出现,并使Cu_(6)Sn_(5)明显细化且弥散分布,添加1%Ni后,Cu_(6)Sn_(5)的细化效果减弱。Sn-15Cu-xNi合金具有高载稳定性与减摩性。在200 N载荷作用下,硬质颗粒起承载作用,而软基体磨损后形成的微小坑洞成为贮油空间,维持了润滑油膜的稳定性。Ni含量为0.5%时,磨损表面的贮油坑洞最均匀细密,致使Sn-15Cu-0.5Ni合金具有最优的磨损性能。

The microstructure and tribological properties of Sn-15Cu-xNi alloy were studied by inductively coupled plasma-optical emission spectroscopy,electron probe microscope analyzer,scanning electron microscope,confocal laser scanning microscope,Brinell hardness tester,and multi-specimen test machine.The results show that the particles in Sn-15Cu alloy are the peritectic structure composed of Cu_(3)Sn and Cu_(6)Sn_(5).Adding 0.1%Ni can refine Cu_(3)Sn and thicken the Cu_(6)Sn_(5) coating layer.Adding 0.5%Ni can completely inhibit Cu_(3)Sn and make Cu_(6)Sn_(5) more refined.The refinement effect of Cu_(6)Sn_(5) is reduced after adding 1%Ni.The Sn-15Cu-xNi alloy exhibits high-load stability and anti-friction properties.Under load of 200 N,the hard particles play bearing role,and the tiny pits formed after the soft substrate wear out become the oil storage space,maintaining the stability of the lubricating oil film.When the Ni content is 0.5%,the oil storage pitting on the worn surface are the most uniform,so the Sn-15Cu-0.5Ni alloy has the best wear performance.